In recent years, demands for high-resolution and high-quality videos have increased more and more in various fields of applications. As pictures have higher resolution and higher quality, the amount of information on the pictures also increases.
With the increase in the amount of data, multi-functional devices and networks with various environments are introduced. With the development of the apparatuses having a variety of performance and the networks having various environments, the same contents may be used with different levels of quality.
Specifically, as terminals are able to support diverse qualities of pictures and various network environments are established, a picture with general quality is enabled in one environment while a higher-quality picture may be available in another environment.
For example, a user having purchased video contents through a mobile terminal can enjoy the video contents on a large-screen display with a higher resolution at his or her home.
In recent years, as high definition (HD) broadcast services are available, a large number of users are getting used to high-resolution and high-quality videos and service providers and service users also pay attention to ultrahigh-definition (UHD) services having a resolution four times higher than HDTV.
Thus, there is a need to provide scalability to video quality, for example, the image quality, resolution, size and frame rate of a video, based on high-efficiency encoding and decoding methods on a high-capacity video so as to offer varied qualities of video services in different environments for users' demands.